Stop 3: La Poruna

La Poruna

Just about 30 miles north of Chui Chui, lie the San Pedro and San Pablo Volcanoes on the right and the La Poruna cone directly ahead.

(Click for a larger view)

La Poruna is a scoria cone on the western flank of San Pedro Volcano. Several lava flows from La Poruna extend westerward for almost eight kilometers! These were mapped in O'Callaghan and Francis, 1986 as part of their work on the San Pedro/Pablo Volcanoes.

The flow is a basaltic andesite with ~59% Silica. Juvenileblock from the flow was dated (via Helium surface-exposure) at 103,000 years (Worner et al, 2000).

La Poruna is one of the primary targets we have been researching as part of a project exploring lava flow morphology in satellite imagery.